The present invention relates in general to a composite article and more specifically to a moldable nonwoven fibrous composite article.
In the fabrication of articles containing polymeric materials which possess sufficient strength and stiffness to function as automobile trunk liners, it is known to take sheets of thermoformable material having different properties, dispose them as layers, and then compress them together under heat and pressure in a mold. At least one layer is used which imparts strength and stiffness and another layer produces bulk sufficient for molding. U.S. Pat. No. 5,298,319 discloses automobile trunk liners fabricated from a fibrous composite having outer layers composed of non-woven fabric consisting essentially of polypropylene staple fiber and an intermediate layer composed of extruded polypropylene. Such prior art fibrous composites are assembled simultaneously with the extrusion of the intermediate polypropylene layer. The inner surfaces of the two outer non-woven fabric layers adhere to the surfaces of extruded polypropylene by the heat generated in the extrusion process and the consequent molten state of adjacent surfaces that melt during the process. With all three layers containing the same polymer, namely polypropylene, eventual recycling of the articles is facilitated.
Several shortcomings are inherent in this prior art procedure. Because the intermediate layer imparting bulk necessary for molding is extruded, articles molded therefrom will necessarily be of uniform thickness. Another shortcoming is that the fibrous composite must be assembled simultaneously with extrusion of the intermediate layer.